Jenkinsfiles

A Jenkinsfile is a text file that defines a Jenkins Continuous Integration and Continuous Delivery (CI/CD) pipeline. It is written in Groovy, a dynamic scripting language, and is typically stored in the root directory of a project's source code repository. The Jenkinsfile describes the entire pipeline as code, meaning that the build, test, and deployment stages are defined in a versionable and auditable way.

There are two syntaxes for Jenkinsfiles: Declarative and Scripted. Declarative pipelines offer a more structured and opinionated approach, providing predefined blocks for defining stages and their configurations. Scripted pipelines, on the other hand, offer more flexibility and allow for complex logic and custom scripting within the pipeline definition.

Using a Jenkinsfile provides several benefits. Firstly, it enables the pipeline to be version-controlled alongside the application code, allowing for tracking changes, rollbacks, and collaboration. Secondly, it makes pipelines more portable, as they can be easily moved between Jenkins instances or projects. Thirdly, it promotes consistency and repeatability in the CI/CD process. When Jenkins detects a Jenkinsfile in the repository, it can automatically configure and run the pipeline. This "pipeline as code" approach is a core tenet of modern DevOps practices.